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What is reproduction?. Reproduction is the process by which organisms produce more of their own kind. Think about it – Without reproduction, all life on earth would no longer exist. What is Asexual Reproduction ?. Only one parent is involved.
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What is reproduction? Reproduction is the process by which organisms produce more of their own kind. • Think about it – Without reproduction, all life on earth would no longer exist.
What is Asexual Reproduction? • Only one parent is involved. • Offspring are genetically identical to their parents. • All cells that come from a single cell are genetically identical to it and to each other; they are all clones. • The new cells are produced by mitosis
Types of Asexual Reproduction Mitosis- is the exact duplication of the nucleus of a cell so as to form two identical nuclei during cell division.
Types of Asexual Reproduction Binary Fission- occurs in one-celled organisms such as the ameba and bacteria. The nucleus divides by mitosis and the cytoplasm divides, forming 2 new daughter cells of equal size.
http://wappingersschools.org/RCK/staff/teacherhp/johnson/visualvocab/BinaryFissionParamecium.jpghttp://wappingersschools.org/RCK/staff/teacherhp/johnson/visualvocab/BinaryFissionParamecium.jpg
Budding • Process by which a new, duplicate plant or animal begins to form at the side of the parent and enlarges until an individual is created. • Very common in plants; • Budding results from an equal division of Genetic information, but an unequal division of cytoplasm or body tissues
Types of Asexual Reproduction Budding - Occurs in Hydra and yeast. The division of cytoplasm is unequal so one of the daughter cells is larger than the other. The daughter cells can separate or remain attached.
Hydra http://www.waycross.edu/faculty/bmajdi/hydra%20budding.jpg
http://judyepstein.com/images/DesertImages/Budding-Purple-LG.jpghttp://judyepstein.com/images/DesertImages/Budding-Purple-LG.jpg
Types of Asexual Reproduction Sporulation - occurs in molds, mosses, etc • Spores are produced in large numbers by mitosis. • Spores are surrounded by a tough coat to help them survive harsh environmental conditions. • Spores usually travel to a new location where they grow into an adult organism
Types of Asexual Reproduction Regeneration- Refers to the replacement or regrowth of lost or damaged body parts • Organisms with undifferentiated tissues are more likely to utilize regeneration
Planaria http://classes.design.ucla.edu/Spring05/152BC/projects/saito/ex3/planaria.jpg
Starfish http://www.vsf.cape.com/~jdale/science/starfishregenerating.jpg
Grafting • Grafting is a process by which two different plants are united so that they grow as one. • Used to make seedless varieties, multiple fruit types per tree…
Cloning • a method of producing genetically identical organisms. • been done with plants for centuries. • examples : cuttings, tubers, bulbs, runners. • in animals and humans it’s more complicated. • cloning raises ethical and moral issues.
Animal Cloning • How its done: • obtain an egg cell from the female of the species to be cloned. • remove the nucleus from the egg cell. • obtain a body cell from the species to be cloned. • remove the nucleus from this cell. • place the nucleus from the body cell into the egg cell. • place this cell into the uterus of the female of the species to clone. • after the normal gestation period, the clone will be born.
Problems with Cloning • Cloning has a low success rate • Cloned organisms often have a shortened life span • Cloning is incredibly expensive